usb: dwc3: gadget: disable U1/U2 on disconnect

If we get a disconnect IRQ, we should take
the core out of low power mode so we can
reconnect afterwards.

Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -1906,19 +1906,16 @@ static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
 
 static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
 {
+	int			reg;
+
 	dev_vdbg(dwc->dev, "%s\n", __func__);
-#if 0
-	XXX
-	U1/U2 is powersave optimization. Skip it for now. Anyway we need to
-	enable it before we can disable it.
 
 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
 	reg &= ~DWC3_DCTL_INITU1ENA;
 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
 
 	reg &= ~DWC3_DCTL_INITU2ENA;
 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
-#endif
 
 	dwc3_stop_active_transfers(dwc);
 	dwc3_disconnect_gadget(dwc);